Hand soap



Patented Apr. 10, 1945 No Drawing. Application .AugustZO, 194.1, Serial No. 407,647

2 Claims.

This invention. relates to manufacture of hand soap; and it includes a soap which is generally useful for cleaning thegrimy hands of mechanics, etc, as well as for removingggrease and dirt from other surfaces contaminated therewith, said soap comprising finely divided :ashes' derived from the combustion of sugar cane bagasse,- one of .the conventional householdsoaps :and usually sufiicient water to form a paste. The invention :also .includes a method of making said hand :soap' which comprises heating amixture of water and :soap to substantially the boiling point, adding .finely divided .ashes of bagasse-and stirring while cooling and'solidifying; allas more fully hereinafter set forthand as claimed.

-A large variety of hand soaps have been :suggested in the art. These soaps in general include various abrasives such .as rfinely divided sand, diatomac'eous earth or the like together with an ordinarysoap and water. It has also been proposed to include in such compositions wood ashes, the ashes of rice ,husksand the like. "These compositions, while successfully-removing grease and dirt, are not satisfactoryzforthe longzcontinueduse owing .to the fact that their-high alkali content, derived from the ashes as well .as from the soap, makes the compositions too harsh, while the abrasive tends to scratch the'hands. With the continued use of such preparations the finger nails become brittle and the hands hard and full of fine scratches in which dirt tends to collect.

I have found that the ashes of bagasse, derived from the combustion of sugar cane, form a highly superior abrasive for inclusion in hand soaps which are free from the disadvantages mentioned. When these ashes in finely divided form are mixed with an ordinary laundry or household soap and sufiicient water to form a paste, a hand soap is produced which can be used over long periods of time without injury to the most sensitive hands. In fact the use of this soap tends to keep the hands soft and the finger nails pliable. While the preparation feels somewhat gritty, it does not scratch the hands.

The cause for this unexpected result is not evident but I attribute the lack of harshness to the fact that the silica present in the bagasse ash is in reactive form, probably forming a silicate gel with the alkali of the soap or at least tending to buffer the same and to reduce its alkalinity. The bagasse ash itself has a low free alkali content. The ash particles areapparently softer than most if not all of the abrasives formerly used in hand soaps and this appears to account for the fact that the hands are not scratched by the use of my scan-even over long periodsrof time. Most of the abrasive particles-of bagasse ash can be crushed between the fingers, much-like lthe particles of an aqueous si-licagel which has been allowed to dehydrate somewhat. "Partof athez-ashes dissolve during use which also .helps to :explain why they do not scratch the hands; But whatever .thetrue explanation :may be, the facts remainas stated.

The composition of the rash usedrinthe present invention is approximately as follows:

I have found that, when bagasse is burned in the usual furnace .of "a sugar factory, while containing its usual water-content of approximately 0% by weight, two types of :ash tare produced. One of these has a .specifiogravity which is sub- .stantially lower than the other and tends to cling to the wall-s of thefurnace, while the heavier portion tends to form in large clinkers in the furnace. The lighter portion is particularly advantageous in the present invention while the heavier portion forms a soap abrasive which is usually too sharp to make a good soap. In the preferred embodiment of my invention, therefore, I separate the lighter portion of the bagasse ash from the heavier portion and use the lighter portion only.

Separation of the lighter ash can be accomplished in various ways. A very simple way is to collect the ash which clings to the walls of the furnace. Bagasse furnaces usually require cleaning once a day and a substantial portion of the ash clings to the furnace walls. Most of this light ash drops from the walls during the cleaning operation. The heavier ash in the bottom of the furnace may be shoveled out and discarded while the portion removed from the walls can be recovered for use in my process. A

The soap employed in combination with the bagasse ash can be of any ordinary variety, such as the usual household or laundry soap. In the better grades of my product castile soap can be employed and it is also possible to employ potash soaps, if desired.

The proportions of bagasse ash to soap and to water which are employed in my hand soap can be varied widely. I usually prefer to produce a product in the form of a paste which requires a water content of at least about 50% by weight. Ifthe soap is to be packaged in collapsible tubes a; somewhat higher content of water is required amounting in some cases to 75%. But even when this proportion of wateris employed the preparation is suficientlys'table so that no segregation of ingredients takes place. If desired, my soap may be formed in cakes having a water content of 25% or less, in which case the inclusion of a small amount of glycerine or the like is advantageous to prevent the soap from drying out. A perfume may be added if desired. The ratio of soap to ashes to be employed depends upon the grade of soap to be manufactured. For the cheaper grades of mechanics soap I usually employ a larger proportion of ashes than of soap, the more expensive grades the proportion of soap can be increased to a point where the ratio of ashes to soap becomes about 1:2.

The bagasse ashes should be present in the soap in finely divided form. This is accomplished by grinding or crushing the ashes followedby screen- .ing them. I prefer to employ the fraction which passes a screen having from 20 to 70 mesh per inch but for the cheaper grades particle sizes up to mesh can be used. I

The soap of the present invention can be produced at a low cost for the reason that bagasse ash has heretofore been considered a waste product. The cost of grinding or crushing the ash followed by screening is low and the step of compounding the soap with the ashes and water is likewise small.

The compounding step is advantageously conducted by introducing the calculated quantity of soap into .the Water at substantially its boiling point. The soap quickly dissolves and then the ashes can be stirred in. During cooling the stirring must be continued until the mass thickens to such an extent that the ashes no longer tend to settle. Since the ashes have a low pecific gravity they have but little tendency to segregate and hence my products are stable even though they may be relatively fluid.

A satisfactory formula for my hand soap is as follows:

Per cent Water 50 Soap (yellow laundry soap) 18 Bagasse ashes (30 mesh) 32 The best proportions to be used in making a hand oap in paste form are about 50 to 60% by weight of water, 15 to 20% of water soluble soap and 20 to 35% of finely sifted bagasse ashes.

the most advantageous embodiments of my invenwhich have been mentioned can be varied substantially without departing from the purview of this invention. It is evident, for example, that the bagasse ash, soap and water can be compounded in any desired manner. It is possible for example to mix the ash and the soap in dry form and then to add the water, heating until the soap is dissolved. The finished product can be packaged in any desired form, the water content being varied to suit. Any of the usual types of soap can be employed and it is even possible to employ soap substitutes in compositions which are sufficiently viscous to prevent the ashes from settling. Other modification of this invention which fall within the scope of the following claims will be immediately evident to those skilled in this art.

What I claim is:

1. A hand soap comprising a water-soluble soap and .bagasse ashes in proportions ranging from about 1:2 to 2:1; said bagasse ashes being in finely divided form, having an alkali metal oxide l a lighter fraction which separates from a heavier fraction of ash upon burning bagasse in a furnace.

JERONIMO DIAZ COMPAIN.

While I have described what I consider to be 

